Umair, thinking that the addition of widgets to the Facebook ecosystem will only result in an "on the order 10% increase in consumption" will prove to be a error on your part.
I can personally tell that the use of widgets has increased my time spent "on platform" (i.e., lending my attention, which Facebook and widgeteers can tax as they determine) by far more than 10%.
And if you're wondering what the platform is about: tt's about strangling potential attention diverters in their cradle, by bringing them onto the platform where Facebook can share in the attention they capture.
E.g., Mark Pincus launched a Poker application that you ties in to the facebook platform. This has effectively dampened the ardour of the marginal entrepreneur to say "Hey, all these poker sites like Party Poker do a crap job of letting you leverage your social graph to play your friends and enjoy poker playing..." and proceed to build that web app, which would then compete with Facebook for "share of waking attention."
The facebook platform, by being "good enough", like MSFT before it, has strangled a lot of probably better pure-play applications in their infancy.
Case in point: I can post my vacation videos to YouTube, or I can post them to Facebook. I choose to do so to Facebook because i know that my friends will get instant distribution of them in their feeds, that commenting is based on a robust identity system, thereby preventing in large part the bile-laden, neanderthal commenting that anonymous commenting typically produces (see YouTube and Digg), and that, guess what, I was already on Facebook when the idea to upload them from my machine hit me.
Sure, I don't think that the Video application yet offers embeds for other sites, and that's a marginal debit compared to YouTube.
But guess what: it's good enough.
Just watch. The hyper-verticalized ad network that MySpace just demod in the NYTimes? Facebook's cooking up the same thing.
Want to pay $100 CPM to deliver a message to Ivy-league grads working who live in San Francisco? Guess who can offer that? Facebook can.
You're VMware and you want to deliver a recruiting video to fully vested Google, Paypal, and eBay engineers living in the Bay Area who are ages 26-34? What sort of CPM are you willing to pay? $200? What's your alternative? A room full of recruiters fully burdened at $50 an hour, scouring linkedin and dialing for resumes? Paying $.20 a pop to get your message to those guys? Or do what Google did: rent a billboard on 101 with a math problem on it for god knows how much a month, in hopes of getting 100 engineers who could answer it? Same outcome. Which one is more effective?
There's a lot to be done here, and Facebook has a lot of brainpower and capital behind it to do it.